Manuscript Summary: It is highly likely that this codex is the original transcription of the neumed manuscript in the hand of Guido von Arezzo commissioned by Abbot Johannes I of Schwanden shortly before 1314. The calligraphic copies found in the other "Schwanden codices" were then produced following this source. Evidence of heavy use indicates that these manuscripts remained in use into the 17th century, that is, until the liturgical reform of the Council of Trent. The forms used are from the Alemannic choral dialect, which is still sung in Einsiedeln today. (lan)